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std::multimap::rbegin,(3) C++ Standard Libary std::multimap::rbegin,(3)

NAME

std::multimap::rbegin, - std::multimap::rbegin,

Synopsis


reverse_iterator rbegin(); (1) (noexcept since C++11)
const_reverse_iterator rbegin() const; (2) (noexcept since C++11)
const_reverse_iterator crbegin() const noexcept; (3) (since C++11)


Returns a reverse iterator to the first element of the reversed multimap. It
corresponds to the last element of the non-reversed multimap. If the multimap is
empty, the returned iterator is equal to rend().


range-rbegin-rend.svg

Parameters


(none)

Return value


Reverse iterator to the first element.

Complexity


Constant.

Notes


The underlying iterator of the returned reverse iterator is the end iterator. Hence
the returned iterator is invalidated if and when the end iterator is invalidated.


libc++ backports crbegin() to C++98 mode.

Example

// Run this code


#include <algorithm>
#include <iostream>
#include <string>
#include <map>


int main()
{
std::multimap<std::string, int> map
{
{"█", 1},
{"▒", 5},
{"░", 3},
{"▓", 7},
{"▓", 8},
{"░", 4},
{"▒", 6},
{"█", 2}
};


std::cout << "Print out in reverse order using const reverse iterators:\n";
std::for_each(map.crbegin(), map.crend(),
[](std::pair<const std::string, int> const& e)
{
std::cout << "{ \"" << e.first << "\", " << e.second << " };\n";
});


map.rbegin()->second = 42; // OK: non-const value is modifiable
// map.crbegin()->second = 42; // Error: cannot modify the const value
}

Possible output:


Print out in reverse order using const reverse iterators:
{ "▓", 8 };
{ "▓", 7 };
{ "▒", 6 };
{ "▒", 5 };
{ "░", 4 };
{ "░", 3 };
{ "█", 2 };
{ "█", 1 };

See also


rend returns a reverse iterator to the end
crend (public member function)
(C++11)
rbegin returns a reverse iterator to the beginning of a container or array
crbegin (function template)
(C++14)

2024.06.10 http://cppreference.com